Often articles or materials are stored or shipped by stacking them one on top of the other with only a thin dunnage or wooden stickers providing spacing therebetween. Common examples of such articles or materials are lumber, plywood, hardboard, or other unpalletized building materials, pieces of which are stacked for drying, storage or transportation and are vertically separated by wooden stickers which are approximately 1 inch or less thick. These stickers are usually placed about 1 to 11/2feet apart along the length of the materials. The provision of the stickers allows for air circulation and ties the load together. However, piles of such materials stacked in this manner, often weigh substantially more than the capacity of a standard forklift, and the entire pile cannot be moved at once. In addition, the piles of materials may be loaded onto vehicles at one facility with a forklift of a capacity sufficiently great to handle the entire stack while they are unloaded at another facility by a forklift having a lesser capacity. Most forklifts, especially those having capacities adequate to lift a stack of undried lumber, have fork arms which have a vertical thickness greater than the 1-inch thickness of the stickers. As a result, the entire load must be lifted at once by the forklift or the pile must be loaded by hand. In the past, in order to overcome the above problems, bolsters or other large dunnage have been placed under the bottom layer of lumber or other building materials, or at appropriate points between the layers. These bolsters are normally 4-inch by 4-inch by 5-foot long timbers and are expensive and difficult to handle. In addition, the placement of these bolsters severely reduces the amount of lumber or building materials which may be stacked in a given height, thus restricting the capacity of the kiln or facility where the material is stored.
Another commonly used solution to the above problem is to place the lumber or other building materials or the stacked articles on pallets. However, most conventional pallets which can be unloaded by a conventional forklift must have strong supporting stringers in order to carry the desired load and provide the 3- to 4-inch clearance beneath the load necessary for fork entry, and the cost of such pallets is often too high to justify shipping it with the materials. In addition, the pallets must be stored with the goods, requiring additional storage space and significantly increasing storage costs. This cost problem in palletized materials is often overcome by the use of disposable pallets without stickers or stringers necessary to provide the desired clearance and which may be formed of corregated materials. An example of such pallets is described in U.S. Pat. Nos. 2,302,137 and 2,328,397. The forks of a forklift must be wedged beneath such a pallet to lift it, and a lift with special chisel forks must be used, or in some cases, the pallet must be pulled onto the fork arms using a special load-pulling device. This chiseling often damages the goods and the load-pulling device requires the use of a very high sheer strength corregated material which is quite expensive.
Inflatable pallets, such as those described in U.S. Pat. Nos. 3,440,976; 3,790,010; 3,913,964 and 4,116,344 may overcome some of the above problems with palletized materials. However, such pallets must still be left with the load during shipping or until the article is used, and these pallets tend to be expensive, increasing handling and storage costs.